Fireworks projectile having distinct shell configuration

Abstract

A system and method for launching projectiles, such as fireworks projectiles, which explode in the air into a pyrotechnic display. The projectile includes a shell constructed from a binding agent and an explosive additive which explodes the shell into small particles. The explosive additive, which may be nitrocellulose, causes the exploded particles to be rapidly burned and consumed to form lightweight, inert flakes that fall harmlessly to the ground. The projectile is aimed and launched by a launcher to rapidly expel the projectile from a launching tube. Once in the air at a predetermined location in the sky, a fuse inside the projectile operates to detonate the projectile into its intended pyrotechnic display. The fuse is extremely accurate and enables detonation of the projectile at precise altitudes. An electronic control system controls launching and detonation of the projectiles in a precise and repeatable manner. The external geometry of the projectile also is configured so that the projectile tumbles when launched and follows a more predictable, repeatable and accurate path in flight.

We claim: 
     
       1. A fireworks projectile for exploding into an aerial fireworks display, comprising: (a) an explosive charge adapted for connection to a detonating fuse, wherein the charge contains a composition adapted to explode into a fireworks display upon ignition by the fuse; and   (b) a shell containing the explosive charge, wherein the shell has a substantially smooth, uninterrupted external surface geometry comprising a substantially cylindrical body having semi-spherical opposing end portions, the external surface of the shell comprising: i) a recess adapted to receive the fuse underneath the external surface of the shell; and   ii) a cover for covering the recess and substantially maintaining the continuity of the external surface geometry of the shell.     
     
     
       2. The fireworks projectile of claim 1, wherein the shell comprises: (a) a first shell half having a semispherical end portion forming a closed end, and a substantially cylindrical section forming an open end; and   (b) a second shell half having a semispherical end portion forming a closed end, and a substantially cylindrical section forming an open end, wherein the open ends of the first shell half and the second shell half are adapted to overlap with respect to each other to form a joint.   
     
     
       3. The fireworks projectile of claim 2, wherein the joint formed by the overlapping portions of the first shell half and the second shell half is secured by an adhesive. 
     
     
       4. The fireworks projectile of claim 3, wherein the adhesive comprises butylacetate. 
     
     
       5. A fireworks projectile for exploding into an aerial fireworks display, comprising: (a) an explosive charge connected to a detonating fuse, wherein the charge contains a composition adapted to explode into a fireworks display upon ignition by the fuse;   (b) a shell containing the explosive charge, wherein the shell has a substantially smooth, uninterrupted external surface geometry comprising a substantially cylindrical body having semi-spherical opposing end portions; and   (c) a priming composition added to the shell to facilitate burning and consumption of the shell upon ignition of the explosive charge, wherein the priming composition comprises a mixture containing a mixing agent and an explosive additive.   
     
     
       6. The fireworks projectile of claim 1, wherein the fuse comprises an electronic fuse. 
     
     
       7. The fireworks projectile of claim 1, wherein the recess is provided in a tube positioned inside the fireworks projectile and extending through the external surface of the shell. 
     
     
       8. The fireworks projectile of claim 1, wherein the shell is constructed from a mixture of a binding agent and an additive, such that upon ignition the shell is exploded along with the explosive charge into small particles that are rapidly burned and consumed. 
     
     
       9. A fireworks projectile for exploding into an aerial fireworks display, comprising: (a) an explosive charge connected to a detonating fuse, wherein the charge contains a composition adapted to explode into a fireworks display upon ignition by the fuse; and   (b) a shell containing the explosive charge, wherein the shell has a substantially smooth, uninterrupted external surface geometry comprising a substantially cylindrical body having semi-spherical opposing end portions, wherein the shell is constructed from a mixture of a binding agent and an additive, such that upon ignition the shell is exploded along with the explosive charge into small particles that are rapidly burned and consumed, wherein the additive is nitrocellulose, and wherein the mixture of the binding agent and nitrocellulose comprises approximately 70 percent nitrocellulose.   
     
     
       10. The fireworks projectile of claim 9 further comprising a launcher having a non-explosive launching medium for launching the fireworks projectile into the air. 
     
     
       11. The fireworks projectile of claim 9, further comprising a launching tube having an explosive burst charge for launching the fireworks projectile into the air. 
     
     
       12. The fireworks projectile of claim 8, further comprising a priming composition added to the shell to facilitate burning and consumption of the shell upon ignition of the explosive charge. 
     
     
       13. The fireworks projectile of claim 12, wherein the priming composition comprises a mixture containing a mixing agent and an explosive additive. 
     
     
       14. The fireworks projectile of claim 13, wherein the mixing agent is acetone and the explosive additive is black powder. 
     
     
       15. The fireworks projectile of claim 14, wherein the priming composition is mixed with the material comprising the shell. 
     
     
       16. The fireworks projectile of claim 14, wherein the priming composition is applied to the inside surface of the shell. 
     
     
       17. The fireworks projectile of claim 1, further comprising a priming composition added to the shell to facilitate burning and consumption of the shell upon ignition of the explosive charge. 
     
     
       18. The fireworks projectile of claim 5, wherein the mixing agent is acetone and the explosive additive is black powder. 
     
     
       19. The fireworks projectile of claim 18, wherein the priming composition is mixed with the material comprising the shell. 
     
     
       20. The fireworks projectile of claim 18, wherein the priming composition is applied to the inside surface of the shell.